Rollup merge of rust-lang#105091 - tshepang:mailmap, r=compiler-errors

add Tshepang Mbambo to .mailmap

... because my surname has changed

```
# before
❯ git shortlog --summary --email | rg Tshepang
   326  Tshepang Lekhonkhobe <tshepang@gmail.com>
     8  Tshepang Mbambo <tshepang@gmail.com>

# after
❯ git shortlog --summary --email | rg Tshepang
   334  Tshepang Mbambo <tshepang@gmail.com>

Author: matthiaskrgr

.mailmap

@@ -532,6 +532,7 @@ Tomas Koutsky <tomas@stepnivlk.net>
 Torsten Weber <TorstenWeber12@gmail.com>
 Torsten Weber <TorstenWeber12@gmail.com> <torstenweber12@gmail.com>
 Trevor Spiteri <tspiteri@ieee.org> <trevor.spiteri@um.edu.mt>
+Tshepang Mbambo <tshepang@gmail.com>
 Ty Overby <ty@pre-alpha.com>
 Tyler Mandry <tmandry@gmail.com> <tmandry@google.com>
 Tyler Ruckinger <t.ruckinger@gmail.com>